While public knowledge concerning the Loetz glassworks continues to improve, many problems remain in the market, not the least of which is the continuing amount of forged Loetz signatures on glass. Many Loetz signatures seen are, unfortunately, forgeries.

Collectors and dealers are urged to familiarize themselves with authentic signatures, to discriminate between the true and false. Signature variations are well illustrated in photographs published in Neuwirth's "Loetz Austria 1900" , "Das Böhmische Glas, Band IV" , and Neue Galerie's "Loetz Bohemian glass 1880-1940" .

Design dates may also be important to remember. If I'm told that a vase  designed in 1906 is signed, I will find that improbable, as nothing was signed after 1903. There are also many decorative types that are more likely to be signed than others. Glass was generally signed based purely on quality. I would not expect to find a signature on a minor Loetz vase, and would be suspicious of one found. Otherwise, I would expect a superb Loetz vase, and most Phänomen pieces to be signed. Some decorations have a quite high signature rate. For example, Loetz experts would recognize the Loetz Phänomen Gre. 29 vase ( listed under "Paris 1900" ) as a vase that is likely to be signed. Statistically, my analysis of this decoration indicates that about 70% of examples were signed at the glasshouse. I would be more suspicious if I found an example that is unsigned!

The authenticity of a Loetz mark can be immediately determined by examining the characteristics of the engraving under high magnification. The engraving tool used by Loetz had a very high vertical oscillation. What appears to be a horizontal line like this _________ , is actually a great number of vertical lines ////////// compressed tightly together.
This produces two immediately recognizable characteristics. The line is going to be thick or broad, as opposed to a thin line. But more importantly, while the line will be dense in areas where the engraver has lingered, other areas will reveal the vertical oscillation of the engraving needle. These vertical striations identify the presence of an authentic Loetz signature, and their absence almost certainly indicates a forgery. This applies to the common Loetz Austria signature, but may be equivocal on the rarer crossed arrows marks because of their design difference. The cited photographs have sufficient resolution for examination and verification of this characteristic ( see the B/W picture at the top of this page ). Web photos generally do not. The vertical striations will be visible in parts of an authentic signature, but not all. Commonly, they are visible in the last _a_ , which together with the broad line, can be seen in the accompanying photos.
.	Authentic Loetz signature (© UK)

Remember to look for the vertical striations, and quickly determine authenticity.

© AJ Alden Jones